JP3951663B2 - Bracket mounting structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a bracket mounting structure, and more particularly to a bracket mounting structure for welding a bracket to a member of a vehicle such as an automobile.
[0002]
[Prior art]
Conventionally, in a bracket mounting structure in which a bracket is welded to a member of a vehicle such as an automobile, a structure as shown in FIG. 4 is known.
[0003]
In the bracket mounting structure shown in FIG. 4, the suspension member mounting bracket 102 is welded to the rear side member 100, and the mounting holes 104 formed in the left and right side wall portions 102A, 102B of the suspension member mounting bracket 102 have, for example, a trailing arm. The arm 106 of the mold rear suspension is pivotally supported by a bolt 108 and a nut 110. As a related prior art, there is JP-A-8-198140.
[0004]
[Problems to be solved by the invention]
However, in such a bracket mounting structure, the left and right side walls 102A and 102B of the suspension member mounting bracket 102 are welded to the left and right side walls 100A and 100B of the rear side member 100 at predetermined intervals by spot welding (welding points). S). As a result, a space for inserting the spot welding gun 111 needs to be secured in the interior 112 of the rear side member 100, and the offset amount between the welding point S and the axis 108A of the bolt 108 serving as a load input position from the rear suspension. M increases. For this reason, the input load F from the rear suspension tends to cause local deformation near the welded portions of the left and right side wall portions 100A and 100B of the rear side member 100 and the left and right side wall portions 102A and 102B of the suspension member mounting bracket 102. In order to improve the above, it is necessary to take measures such as increasing the thickness of the rear side member 100 and the suspension member mounting bracket 102 or adding a reinforcing member, which increases the weight.
[0005]
In view of the above facts, the present invention has an object to obtain a bracket mounting structure capable of improving the joint rigidity and joint strength in the welded portion without increasing the weight.
[0006]
[Means for Solving the Problems]
The present invention according to claim 1 is a side member having a U-shaped cross section having corners at both left and right end portions of a flat surface portion which is a bottom portion with the opening portion facing upward.
Is the front wall portion and the left and right side wall portions to the vehicle rear side opening made to have U-sectional shape, the laser over the substantially entire region of the left and right side wall portions the ridge side wall portions of the left and right is formed by the corners of the side members A suspension in which the upper edge of the left and right side wall portions is line welded over substantially the entire area of the left and right side wall portions by laser welding in parallel with the line welding in the vicinity of the ridgeline of the side member. A member mounting bracket;
And an input load to the suspension member mounting bracket is supported by a flat portion of the side member.
[0007]
Accordingly, by setting the welded portion with the suspension member mounting bracket at the ridge formed by the corner portion of the side member, the offset amount between the point of application of the input load to the suspension member mounting bracket and the welded portion is reduced. Further, the input load to the suspension member mounting bracket can be supported by the flat surface portion of the side member adjacent to the ridgeline. Further, the welded portion between the ridgeline formed by the corners of the side member and the left and right side wall portions of the suspension member mounting bracket is subjected to line welding by laser welding over substantially the entire left and right side wall portions, and in the vicinity of the ridgeline of the side member. Since the upper end edges of the left and right side wall portions of the suspension member mounting bracket are line welded over substantially the entire left and right side wall portions by laser welding in parallel with the line welding, the welded portions are welded at predetermined intervals by spot welding. Compared to the case, it is possible to improve the joint rigidity and the joint strength at the welded portion between the side member and the suspension member mounting bracket without increasing the weight.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
One embodiment of the bracket mounting structure according to the present invention will be described with reference to FIGS.
[0013]
In the figure, the arrow FR indicates the vehicle front direction, the arrow UP indicates the vehicle upward direction, and the arrow IN indicates the vehicle width inside direction.
[0014]
As shown in FIG. 2, the bracket mounting structure of this embodiment is applied to a rear side member 10 as a member. The rear side member 10 is a pair of left and right along the front and rear of the vehicle in the vicinity of both lower ends in the vehicle width direction. (The rear side member on the right side of the vehicle is not shown).
[0015]
As shown in FIG. 1, the cross-sectional shape of the rear side member 10 is a U-shape having corners 10F and 10G at both left and right ends of a flat surface portion 10E that has the opening facing upward in the vehicle, and is in the vehicle width direction. A flange 10B is formed at the upper end edge of the outer side wall 10A toward the outside in the vehicle width direction, and a flange 10D is formed at the upper end edge of the side wall 10C at the inner side in the vehicle width direction toward the inner side in the vehicle width direction. ing. These flanges 10 </ b> C and 10 </ b> D are welded to the lower surface 12 </ b> A of the rear floor panel 12, and a closed cross-section portion 14 extending in the vehicle front-rear direction is formed by the rear side member 10 and the rear floor panel 12.
[0016]
As shown in FIG. 2, a suspension member mounting bracket 16 as a bracket is disposed on the flat surface portion 10E side of the rear side member 10, and this suspension member mounting bracket 16 has a U-shaped cross section that is open at the rear side of the vehicle. It has become. Further, attachment holes 18 are formed in the lower portions of the left and right side wall portions 16A and 16B of the suspension member attachment bracket 16, respectively.
[0017]
As shown in FIG. 1, for example, the tip 20 </ b> A of the arm portion 20 of the trailing arm type rear suspension is pivotally supported by a bolt 24 and a nut 26 in the mounting hole 18 in the suspension member mounting bracket 16. Reference numeral 27 in the figure denotes a washer.
[0018]
The left and right side wall portions 16A, 16B of the suspension member mounting bracket 16 are line-welded by laser welding (welded portion P1) to the ridgelines 30, 32 formed by the corner portions 10F, 10G of the rear side member 10 and extending in the vehicle front-rear direction. ing. In addition, upper end edges 16C and 16D of the left and right side wall portions 16A and 16B of the suspension member mounting bracket 16 are lined by laser welding at portions near the corner portions 10F and 10G in the side wall portions 16A and 16B of the rear side member 10. It is welded (welded part P2).
[0019]
As shown in FIG. 2, the upper edge of the front wall portion 16E of the suspension member mounting bracket 16 is line welded (welded portion P3) to the flat surface portion 10E of the rear side member 10 by laser welding.
[0020]
Next, the operation of this embodiment will be described.
[0021]
In this embodiment, the welded portion P1 with the suspension member mounting bracket 16 is set on the ridge lines 30 and 32 formed by the corner portions 10F and 10G of the rear side member 10, so that the input load to the suspension member mounting bracket 16 (FIG. The offset amount L1 between the axis 24A of the bolt 24 and the welded portion P1, which is the action point of the arrow 1), becomes small. Further, the input load F to the suspension member mounting bracket 16 can be supported by the flat surface portion 10E of the rear side member 10 adjacent to the ridge lines 30 and 32. As a result, it is possible to improve the joint rigidity and joint strength in the welded part P1 without increasing the weight.
[0022]
Further, in the present embodiment, the upper edge portions 16C and 16D of the left and right side wall portions 16A and 16B of the suspension member mounting bracket 16 are line-welded by laser welding (welded portion P2) in the vicinity of the corner portions 10F and 10G of the rear side member 10. Therefore, the offset amount L2 between the axis 24A of the bolt 24 and the welded portion P2, which becomes the action point of the input load (arrow F in FIG. 1) to the suspension member mounting bracket 16, is reduced, so that there is no increase in weight. The joint rigidity and the joint strength at the weld P2 can be improved.
[0023]
Moreover, in this embodiment, since the weld parts P1 and P2 are line-welded by laser welding, the joint rigidity and joint strength at the weld parts P1 and P2 are improved as compared with the case of welding at predetermined intervals by spot welding. it can.
[0024]
Furthermore, in this embodiment, the suspension member mounting bracket 16 is line-welded by laser welding to the ridge lines 30 and 32 formed by the corner portions 10F and 10G of the rear side member 10, so that as shown in FIG. The weld beads 36 and 38 are formed between the suspension member mounting bracket 16 and the suspension bead 16. As a result, it is possible to suppress the deformation of the left and right side wall portions 16A and 16B that are generated by the input loads (arrows F1 and F2 in FIG. 3) applied to the suspension member mounting bracket 16 by the weld beads 36 and 38.
[0025]
Although the present invention has been described in detail with respect to specific embodiments, the present invention is not limited to such embodiments, and various other embodiments are possible within the scope of the present invention. It will be apparent to those skilled in the art .
[0026]
【The invention's effect】
The present invention according to claim 1 is a side member having a U-shaped cross section having corners at both left and right end portions of a flat portion which is a bottom portion with the opening facing upward, a front wall portion, and left and right side wall portions. The left and right side wall portions are line welded by laser welding over substantially the entire area of the left and right side wall portions to the ridge formed by the corner portions of the side members. A suspension member mounting bracket in which the upper end edges of the left and right side wall portions are line welded over substantially the entire area of the left and right side wall portions by laser welding in parallel with the line welding. Because the input load of the side member is supported by the flat part of the side member, the joint rigidity and strength at the welded part between the side member and the suspension member mounting bracket without increasing the weight. Has an excellent effect can be improved. Moreover, it has the outstanding effect that the joint rigidity and joint strength in a welding part can be improved compared with the case where it welds by predetermined intervals by spot welding.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a bracket mounting structure according to an embodiment of the present invention as viewed from the front of a vehicle.
FIG. 2 is a perspective view showing the bracket mounting structure according to one embodiment of the present invention as seen from the obliquely rearward outside of the vehicle.
FIG. 3 is a cross-sectional view showing a bracket mounting structure according to an embodiment of the present invention as seen from the front of the vehicle.
FIG. 4 is a cross-sectional view of a bracket mounting structure according to the prior art as seen from the front of the vehicle.
[Explanation of symbols]
10 Rear side member (member)
10A Rear side member side wall 10C Rear side member side wall 10E Rear side member flat surface 10F Rear side member corner 10G Rear side member corner 16 Suspension member mounting bracket (bracket)
16A Side wall portion 16B of suspension member mounting bracket Side wall portion 20 of suspension member mounting bracket Rear arm arm portion 30 Rear side member ridge line 32 Rear side member ridge line

Claims (1)

A side member having a U-shaped cross section having corners at both left and right end portions of the flat portion serving as a bottom portion with the opening facing upwards of the vehicle;
The front wall portion and the left and right side wall portions are formed into a U-shaped cross-sectional shape having an opening on the rear side of the vehicle, and the left and right side wall portions are laser beams over substantially the entire area of the left and right side wall portions on a ridge formed by the corner portions of the side members. A suspension in which the upper edge of the left and right side wall portions is line welded over substantially the entire area of the left and right side wall portions by laser welding in parallel with the line welding in the vicinity of the ridgeline of the side member. A member mounting bracket;
And a bracket mounting structure, wherein the input load to the suspension member mounting bracket is supported by a flat portion of the side member.

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